FOREST INSECTS AND FUNGI 123 



mer work from near the surface to ten or twelve inches below; 

 in late fall and winter they bore much deeper and remain there 

 until frost leaves the ground. They work at night and will be 

 found nearer to the surface then than during the daytime. 



In August or September the grubs begin to change into beetles, 

 and as such remain in the ground until spring, when they emerge 

 and are a familiar sight. Many remain in the grub stage for 

 more than one season, and do not change into beetles until the 

 second August or September. This gives them a longer time to 

 feed, and as they grow in size they become more injurious. Often 

 they work until the ground is frozen and start in early again 

 when it thaws in the spring. 



Treatment. A simple and cheap method of combating the 

 June bug has not yet been worked out. At present in forest 

 nurseries, when the grubs are found to be abundant, they are 

 dug out by hand, the spot where they are working being easily 

 determined by the appearance of the injured plants. This 

 method can be used in transplant beds, but in thick beds of 

 seedlings it is hardly practicable. Where land known to be 

 infested with the grub is to be used for a nursery or a plan- 

 tation, it is a good thing to turn in swine. They will uproot 

 and eat the grubs thoroughly. After that the field can be used 

 safely. 



Inasmuch as old sod and grass land is preferred by the beetles 

 as a meeting place, such land should not be put into nursery 

 use until after a year or two of preliminary cultivation. 



In the case of a similar species, trapping and killing the beetles 

 has been tried in Europe sometimes very successfully. In one 

 section where the insects abounded, the cost of planting was in 

 eight years reduced from the abnormal figure of $53 per acre to 

 between $3 and $4 per acre. In this case trap trees of a species 

 which the beetles preferred were left in the open, and then 

 the beetles, when in the trees, were shaken down upon sheets 

 and destroyed. 



